Re: Salvo Missles vs. MT missiles

Welcome to the list!

Warning: I often express myself quite bluntly and/or cynically. Don't
take 
it as personal hostility; I'm like this against *everyone* including Jon

Tuffley himself.

Thomas Westbrook wrote:

>As player of Full Thrust and new to the GZG mailing list (I apologize
if 
>this is a redundant topic). Why does the Fleet Book use salvo missiles 
>instead of the more potent, in my opinion, MT missiles. Is this part of
a 
>NWO conspiracy to have new systems that are inferior to the systems
they 
>replace and call them an improvement?

Nope. MT missiles under the current rules (MT+FB1+FB2) aren't
particularly 
powerful - they're easy to dodge at least in Cinematic (since they can
only 
be launched into the launching ship's (F) arc and are about as
manoeuvrable 
as thrust-2 Cinematic-moving dreadnoughts on their 2nd and 3rd turns of 
flight), easy to outrun (since their max speed is a paltry 18 mu/turn)
and 
easy to shoot down (PDS and Pulsers hit them on 4+, Class-1 Beams and 
K-guns hit them on 5+, scatterguns and interceptor pods kill them 
automatically - more on this below). If the MT missiles manage to reach
a 
target in spite of all those handicaps they can hit it hard, but that's
one 
mighty big "if" to get past first.

>As I learned to play with MT missiles, I got pretty good at launching
at 
>60mu and hitting at 40+mu, well out of the range of retaliation from
the 
>opposing force.

In that case you either used house rules giving the missiles a vastly 
improved manoeuvre abilities, or your opponents had no clue about how to

avoid them.

If you had played against me using the MT rules and you had launched
that 
far out, none of your missiles would've hit: if you launch ~60 mu out
and I 
turn away your missiles will run out of endurance and expire before they

reach me, and if I don't turn aside I have plenty of space and time to 
build up a velocity which allows me to overfly them. (With their "one 
60-degree turn at the mid-point of their move" they can't turn back to 
engage me once I'm past them, and with a mere 18-mu move they're easy to

overfly.) Been there, done that plenty of times.

>Statistically speaking, the salvo missile pack will lock on with about
3.5 
>missiles and the
>defender's PDS will shoot down 3.5 missiles, therefore hitting on
average 
>with NONE.

Ouch. Two bad mistakes in one sentence, combining to give a completely 
false image :-/

Mistake number one: if each salvo missile pack locks on with 1D6
missiles 
and each PD weapon shoots down 1D6 missiles from the salvo it targets,
you 
still get a *positive* average number of missiles getting through -
because 
the *lowest* number of missiles that gets through is zero (you can't
shoot 
down more missiles than there are lock-ons), and you also have a number
of 
cases where the PD rolls low and the missile salvo rolls high:

Number of missiles getting through for the various combinations of
lock-on 
and PD rolls:
		 PD roll:
Missile roll:	   1	  2	 3	4      5      6
1			0      0      0      0	    0	   0
2			1      0      0      0	    0	   0
3			2      1      0      0	    0	   0
4			3      2      1      0	    0	   0
5			4      3      2      1	    0	   0
6			5      4      3      2	    1	   0

IOW, with 1 D6-rolling PD weapon vs 1 missile salvo there are 36
possible 
outcomes, of which 21 result in zero missiles locking on - but the other
15 
outcomes have one or more missiles getting past the PD weapon, and the 
actual *average* number of missiles hitting is 35/36. The only way to
get 
an *average* of zero missiles getting past this kind of PD weapon is to 
fire 6 (or more) of these weapons at each salvo - otherwise there's
always 
the chance, albeit small, that the PD weapons will all roll '1' while
the 
salvo rolls a '6'.

Second (and worse), *PDS* doesn't shoot down on average 3.5 missiles
from a 
single salvo unless you fire around 10 PDSs against it! While there are
PD 
weapons which shoot down 1D6 missiles (the Kra'Vak scattergun and the 
Sa'Vasku interceptor pod, both from FB2), the FB1 PDS isn't one of them;

instead it fires a *beam* die: rolls of '1', '2' or '3' have no effect, 
rolls of '4' or '5' destroy one missile from the salvo, and rolls of '6'

destroy two missiles and allow a re-roll. If there had been an infinite 
number of missiles in the salvo, the PDS would shoot down on average 0.8

missiles per shot

Thing is, a salvo *doesn't* have an infinite number of missiles; it only

has 6 missiles, and most of the time not all of those 6 missiles will
lock 
on. Any PDS hits that exceed the number of locking-on missiles in the
salvo 
are simply wasted - they don't carry over to the next salvo. Because of 
this a single PDS firing at a salvo missile salvo shoots down on average

~0.7 missiles from it, and the more PDSs you throw at a single salvo the

fewer missiles each one of them will shoot down. The *total* number of 
missiles killed will of course go up when you throw more PDSs at the
salvo, 
but it isn't as simple as saying "2 PDSs will shoot down on average 1.4 
missiles" because they're going to steal each others' kills - instead 2 
PDSs shooting at a single missile salvo will shoot down on average 0.66 
missiles each (for a total of ~1.3 missiles killed), 3 PDSs against a 
single missile salvo take out on average 0.6 each (for a total of 1.8 
missiles killed), and so on.

>  MT missiles, that are shot down on a 6 on 1D6,

And a third mistake: here you are confusing the PDAF and ADAF systems
from 
the basic FT2 rulebook with the PDS introduced in FB1.

PDAF and ADAF shoot down MT missiles on rolls of '6' on 1D6. However,
none 
of the ships in FB1 have PDAF or ADAF; they all have PDS instead - and 
that's a different system, with different rules.

According to FB1 p.7 PDSs kill *missiles* - not just the Salvo variety,
but 
*any* missiles including the MT ones - on rolls of '4' or better. Since
the 
MT missiles don't fly grouped in tight salvoes each of them counts as an

individual target, so even a PDS roll of '6' can only shoot down one
single 
MT missile; but a 50% kill probability per PDS is pretty nasty to the 
missiles anyway.

FWIW work is being done to update the MT missiles to Fleet Book status;
the 
UNSC AMTs is a variant of them. The UNSC beta-test rules and designs can
be 
found via the "Links" page on the GZG site.

Regards,

Oerjan
oerjan.ohlson@telia.com

"Life is like a sewer.
  What you get out of it, depends on what you put into it."
-Hen3ry